diatom

[dahy-uh-tuh m, -tom]

noun

any of numerous microscopic, unicellular, marine or freshwater algae of the phylum Chrysophyta, having cell walls containing silica.

Nearby words

Origin of diatom

1835–45; < New Latin Diatoma originally a genus name, feminine noun based on Greek diátomos cut in two. See dia-, -tome

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for diatom

It is necessary to avoid any air current which will cause the diatom to fall from the thread.
The Diatomaceae of Philadelphia and Vicinity|Charles Sumner Boyer
Thus Pseudocerataulus Kinkeri is a diatom which cannot possibly be seen without the use of a microscope.
The Romance of Plant Life|G. F. Scott Elliot
This diatom is often found in abundance in the water supplies of cities.
Through a Microscope|Samuel Wells
The diatom itself may be washed in the same way, if it is not too small.
The Diatomaceae of Philadelphia and Vicinity|Charles Sumner Boyer

Diatom ooze is the characteristic deposit in high southern latitudes.
Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 8|Various

British Dictionary definitions for diatom

diatom

noun

any microscopic unicellular alga of the phylum Bacillariophyta, occurring in marine or fresh water singly or in colonies, each cell having a cell wall made of two halves and impregnated with silicaSee also diatomite

Word Origin for diatom

C19: from New Latin Diatoma (genus name), from Greek diatomos cut in two, from diatemnein to cut through, from dia- + temnein to cut

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for diatom

diatom

1845, coined from Greek diatomos "cut in two," from diatemnein "to cut through," from dia- "through" (see dia-) + temnein "to cut" (see tome). So called because they typically appear to have been cut in half. Related: Diatomic.

Science definitions for diatom

diatom

[dī′ə-tŏm′]

Any of various one-celled aquatic organisms of the class Bacillariophyceae that have hard bivalve shells (called frustules) composed mostly of silica, can perform photosynthesis, and often live in colonies. They make up a large portion of the marine plankton and are an important food source for many aquatic animals. The skeletal remains of diatoms are the main constituent of diatomite.